05/21/2012 08:18 am ET Updated Jul 21, 2012

Introducing The 30-Day Summer Shape Up Challenge: Sweat Into Summer

Are you sitting down?

That's precisely the problem.

Between long commutes, desk jobs and thousands of TV channels, Americans are more sedentary than ever. A 2007 study found that on average, we sit for nearly eight of our waking hours. And all that sitting is hurting our health. It ups diabetes risk, could raise cancer risk and increases your likelihood of dying of any cause. It's also making your butt bigger -- and not in a good way.

We're not all going to turn into bike commuters who work at standing desks overnight. But just a little bit of extra movement can make a big difference, and every little bit counts. Even something as simple as bending over to tie your shoe is better than just sitting, the New York Times reported.

That's the idea behind our 30-Day Summer Shape Up Challenge. We're no strangers to the sedentary lifestyle, but we want to do something about it. Which is why we're not asking you to lose 10 pounds or two sizes or however many inches you think you'd look better without. Rather than tell you how to look bangin' in that bikini (although that might be the end result, anyway!), we're asking you simply to move more. All you have to do is sweat, even just a little, every day, from now until the official start of summer, June 20.

Let me tell you what I'm planning to do. I have this thing about triceps. I want them. Like, really want them. Maybe not quite Madonna triceps, but definitely Michelle Obama triceps, and maybe even Jessica Biel triceps. I know I need to move them more, but I have found plenty of excuses not to. I'm joining the 30-Day Summer Shape Up Challenge with the intention of strutting into the office on June 20, guns blazin'. I've decided, for me, that means 20 pushups -- and not those lazy ones, either, these ones here with perfect form -- every day.

You don't have to share my same nutty must-have-triceps mentality. If you have a workout you love, great! Keep doing that a few times a week, and mix in some other ways to sweat! Or, try a new way to sweat every day and find what you like. Or, choose something you can do every day, like pushups, and challenge yourself to meet a concrete goal.

Join the 30-Day Summer Shape Up: Sweat Into Summer Challenge NOW!

To help you stay motivated and to guide you toward new workouts, classes and sports you may never have thought to try, we've asked some fantastic trainers, fitness instructors and HuffPost bloggers to tell us about their favorite ways to sweat every day, new ways to sweat they're dying to try and ways to sweat they think you'll enjoy. Along the way, let us know in the comments of their posts how your daily sweating is going, send us pictures of your progress, or gripe when you don't feel like getting your hair sweaty. We'll also be checking in on Facebook and Twitter using the hashtag #sweatintosummer. We'll keep each other on track, and when summer rolls around, we'll be better for it. Happy sweating!

Missed It? You can still participate in the 30-Day Summer Shape Up:

For more by Sarah Klein, click here.

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